Shortgrass prairie. It’s what used to cover a large part of eastern Colorado, up to the foothills. Comprising a plethora of flora and fauna, our prairie grasslands are now listed as one of the most endangered biomes in the world. Indigenous people cared for this delicate, yet rugged, ecosystem with careful awe as it was home to large herds of bison, elk, deer, and pronghorn - main food sources for their people. We now know that these animals, as well as the thousands of other species that live, feed, breed, and migrate here, were key to maintaining the plants and earth below their feet. With 90 percent of their biomass below ground with deep roots,
these prairies are a vital carbon sink consuming one fourth of the carbon dioxide pollution produced by humans worldwide. In fact, according to a study from the University of California, Davis, grasslands and rangelands are more resilient carbon sinks than forests because they are impacted less by droughts and wildfires.
Carbon sinks are natural deposits of carbon into the earth, which reduces the carbon dioxide in the air. Plants, in this case, absorb carbon from the air through photosynthesis, storing much of it in their cell structures and return oxygen back to the atmosphere. While you’d think that trees, providing a large above ground structure that goes through photosynthesis, would be more efficient than grass and prairie plants. However, when we look at the entire structure and number of these plants on our prairies, you’ll learn that what you DON’T see is what is important. In fact, native bluestem grass may have roots that reach five to 12 feet underground.
In the 1930s, the fast and furious Agricultural farming of the previous decade tore up these plants, exposing the soil. The deep roots that trapped the soil and protected against erosion and drought contributed to the drought in that time, causing a Mars-like landscape void of life. You see, the roots were deep for a reason. Perennial plants with deep roots can withstand long periods without rain: they reach deep into the cool soil to tap into underground water resources AND store water for longer periods of time. They also allow fast regeneration from brush fires and large herds of grazing animals because only the tops of these plants are disturbed. These vital plants also provided vital habitat for pollinators and birds that are pivotal in sustaining food sources for these herds.
The dust bowl was one of the most devastating environmental disasters in US history. With these newly created vast deserts across the land (13 million acres), water became even more scarce and livestock and people began to suffer, crops were unsustainable, and the earth rose up to swallow entire towns. This then sparked a mass migration out of Colorado (and surrounding states) due to the unsustainability of the land. To this day, our farmers suffer from modest drought conditions every few years and massive droughts every 20 years. Plowing of native grasslands and long-term crop production result in approximately a 50% loss of soil organic carbon - and in the short-grass steppe region of northeast Colorado, 60 years of cultivation resulted in 62 percent less soil organic carbon. It is estimated that this loss occurred in the first three years of cultivation. Scientists are now showing models that indicate it will require hundreds of years to repair. Very simply put (and not going into the devastating effects of N2O emissions caused by cultivation and application of nitrogen fertilizers), the loss of our native grasslands is of major concern in climate change.
Today, the practice of crop rotation and other more sustainable farming techniques have helped maintain earth health. More good news: The American Prairie Reserve is working on acquiring and conserving intact grasslands across the region (managing deeded lands, collaboration with public land agencies, and technical assistance and financial incentives for private landowners) has generated a plethora of environmental positives for the approximately 450,000 acres it oversees. Still, with large areas of monocultures (cultivated land including agriculture and urban development), we have more to consider. Without a change in our earth care, even on a small, personalized, scale, climate change will continue to be a great threat.
What can you do?
Assuming you live in suburbia, here are a few things you can do help create a more balanced ecosystem and sustainability:
Replace Kentucky bluegrass or non-native fescue grasses with buffalograss or perennial ryegrass. Both of these grasses are considered low-maintenance, deep root (drought tolerant) and turf forming. Buffalograss even requires infrequent mowing - that’s good for the wallet and the environment. Their long-dormant season, however, has kept them from being at the forefront of urban landscapes - especially neighborhoods with HOAs.
Reduce the amount of turf on your property by planting native and adapted drought-tolerant shrubs and perennials. If the word “xeriscape” brings forth visions of gravel and cactus, you’re off track. With a large range of sustainable and native plants available that are specifically cultivated or suited to our climate and soils, you can have the easy, low-maintenance cottage garden of your dreams.
Intersperse native and adapted flowering perennials in your flower borders or between your vegetable plots. Plans such as prairie coneflower, Indian blanket flower, and prairie gayfeather can attract pollinators and deter pests. Consider adding scented shrubs like buffalo currant or english lavender (though not native - a drought-tolerant and low-care herb that is great for bees) around patios or near windows and doors.
Introduce container gardening to your existing landscape. You can grow many beneficial and native wildlife attracting plants in containers where space is limited. Consider mints, alliums, and asters for long-blooming, low-maintenance color. With a little adjustment to the potting soil composition, these plants can thrive.
Line your driveway or sidewalks with native, tall, clumping grasses like blue grama (my favorite cultivar is ‘Blonde Ambition,’ switchgrass (I love ‘Heavy Metal’), or the native little bluestem.
It may seem like small potatoes, but if everyone does just a little bit to support our native ecology, we can reduce carbon, reduce the need for fertilizers, reduce our water usage, and support the animals and insects that keep our climate balanced.
For more information on the ecological effects of prairie loss, go to: https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.1625